Rotary concrete pump



Dec. 2, 1952 c. l. LONGENECKER ROTARY CONCRETE PUMP Filed Oct. 14, 1948 2 SHEETS-SHEET 1 CHARLES l. LONGENECKER INVENTOR.

TTORNEV 1952 c. l. LCJNGENECKER 2,619, 13

ROTARY CONCRETE PUMP Filed Oct. 14, 1948 2 Sl-IEETS-SHEET 2 17 i 6 J6 3 ==Z 3 CHARLES I. LONGENECKER INVENTOR.

Patented Dec. 2, 1952 UNITED STATES =OFFICE 7 ROTARY CONCRETE PUMP Charles I. Longenecker, Wauwatosa, 'Wis., as-

;signor to Chain Belt Company, Milwaukee, Wis a corporation 10f Wisconsin nApplicationO'ctober 14, 1948, Serial No: 54,371

sideration thepeculiarities ofcconcrete as a pumpable medium.

This invention isdirectedto the provision of a rotarypumpin-which the elements are arranged and operated in 1amanner that will enable the machine to pump concrete.

HA rotarypumphas a number of advantages in p p g concrete as well as other materials, ari-singvrprincipally :from its light weight, large capacityand simplified-construction. These advantagescare particularly advantageous for con-- crete pumpingsystems since the only: existing successful concrete pump, Whichis of the reciprocating piston type, is both heavy and expensive ,by..comparison.

' With a, reciprocating piston pump, the mass of concrete in the pipeline comes to \restat each .reciprocationiofthe piston, whereas with arotary pump, thelflow is continuousflenablingthe use of longer pipelines .without building 1111) excessive pressure.

1 Reduction of the vsize of the, pump .is Elikewise of, great importance since .it enables "the ump to ,be utilizedin confined quarters where the present reciprocating piston ,typ-e pump. cannot behemplayed.

According .to the present invention, a more or fless conventional arrangement of rotor and stator is used, with oscillating .or vibrating impeller memberst'mounted ,on the rotor toiiunction in. a generally "well known manner. llPeculiarities .{of construction arise from the requirement ofqmaintaining 'within the workingHcham-ber pressure 'whichxmay'be well in excessbf, 100 .lbs. per sq. inch; createdby a moving stream of material 'which' embodies stones and the other coarse,

"abrasive constituents of aconcrete mixture; TUnless'the pump canjrun efficiently for a reasonably longpribdxdf time withoutthe replacement of wearing parts, it is not, a practical htoolliorlthe placement Iofconcrete.

.Oneiof the featuresnbf this-invention is the v provision of arrotary pumpin which the impeller ,members are caused. to move .between two wexitreme v positions-1 during therotation-ofrthe-pump, but the drive of [the impellers in one direction,

i.-:@1e., toward non-impelling position, is positive,

whereasathe drive in the opposite direction, as

the impeller members are brought into operating the vimpeller members encounter a an obstruction such as a-stonein-the concrete being pumped.

"It is highly importantlthatthe impeller members be required to move in orderthat'theirtend- H ency to stickin the presence ofa pasty material such as concrete may not. be aggravated, and by this invention,- whiletravel is limited in one directionto a certain predeterminediextent, itis positive up to thatpoint; and it also positivejinlreturn an-d hence :the .partsrcannot .ffreezetin any aoneflposition. In practicethe amount of relief or ,overtravei that is permitted during the movement of the impeller members into thewrotor runneris of the sameorder as thelargest stone permitted-in the concrete beinghpumped.

While :theimpeller members are 'yieldably i driven in one. direction as indicated. above, the arrangement of these members and their operation .is suchlthat the -yie1-dingof onenof the im- ,pellers under such-circumstances does not impair l-theiefiiciency of-the pump or. create channelling of the concrete minuthe working chamber. This results fromthe improbability of two successive .imp'eller anembers each encountering ..a similar obstruction, the ..nature :of concrete "as a .semipl-asticflfiu'id, and..the1 drive of the impeller "mem- .bersras aforesaid,.a11 cooperating to maintaina steady, substantially uniform, rate of. flow of neonrcrete throughthepipeline.

'The invention; is illustrated in the accompany- .ing drawings wherein:

Fig. l :is an end. elevationtakenin'section through the center of the impeller members;

.,Fig. 2iisiani-end elevation looking .in thaop- 'positeldirection from "Fig.1,1, with partstbroken W away .to'r'illustrate lthe impeller actuating .mcha- )msm;

Fig. 3 is a section taken on line 3-3 ofEiglL; Fig. .4 is an enlargedview of one ofthe impeller actuating mechanisms;

' Fig. 5 .is. an. exploded side elevation. iof'hfthe tmecha'nismshown inEig. .4 ;.,and

This 6.. is. a section showing an enlargement "or elementsshowninFig. 3.

In .the drawings the shaft 1 I, driven -.;by-;any suitable source .of; power, hasasplined thereon the cylindrical :rotor 112, WhiGhfiS preventedtfrom moving axially=,of the shaft by the .ishoulder 13 ,on onevside of-thelretorqandz by" thelock-inut A 4 on the 1 othertside. The cross sectional: shape of the'rotor -is' best illustrated inwFig. 3.-from which it will be apparent, as illustrated in the lower portion of said figure, that the outwardly extending, substantially radial flanges l5, combined with the rotors intermediate cylindrical surface 18, constitutes a runner in which material is propelled through the pump.

Enclosing the rotor runner is the housing generally designated H which may be mounted on a skid base or a vehicle as the occasion demands. The housing I"! has an inlet opening is and an outlet l9 separated by a stripping element 20, best illustrated in Fig. 1. By providing the inlet [8 above the rotor, gravity is utilized to facilitate charging of the pump, while the location of the outlet I9, also above the rotor and adjacent the inlet, makes possible the use of substantially the entire volume of the rotor runner as a working chamber.

The stripping element corresponds in shape to the cross section of the rotor and substantially occupies the same, with the edge 2| of the stripper adjacent the cylindrical surface is of the rotor curved to conform closely thereto.

The rotor l2 carries four movable impeller members 22, each being identical in construction and in method of mounting and operation. The impellers 22 are cylindrical plugs having a central channel portion 23 so that when in one position, the opening which the channel portion provides corresponds to the cross section of the rotor runner and enables the impellers to pass the stripping element 20 without interference. In this position, the impeller is substantially wholly recessed in the rotor, the rotor having four axial grooves 24 in its periphery to accommodate the entire solid, central portion of the respective impeller members.

Extending from either side of the impellers are trunnions 25 journalled in bearings 26 carried by hub'brackets 21 bolted on the sides of the rotor 12. The rotor I2 is somewhat wider than the cylindrical portion of the impeller members, and as' a result, the side flanges E5 of the rotor are bored out to accommodate the ends of the impellers and the sealing members 28 disposed therebetween. This construction enables the removal of the impellers by sliding them endwise following the removal of the bolts 28' and the bearing brackets 21 which these bolts retain.

The'disposition of the seals 23 is best illustrated in Fig. 6, wherein there is also shown the seals 3a which are located between the stator portion 3| of the housing I! and the two edges of the rotor runner, the latter having outwardly turned cylindrical flanges 32 against which the seals bear during rotation of the rotor. A replaceablelining member 33 mounted on the inside of the stator extends into the rotor runner a slight distance and reduces the amount of a hub portion 38, which is free to turn on an axis concentric with the axis of the impeller. In the present instance, the roller 36 is integral with a stud 39, the threaded end of which cooperates with a nut 40 and lock washer t] to retain the stud in its journal in the arm 37.

The hub 38 is journalled on a second hub 42 locked on the trunnion 25 of the impeller member by a key 43. Hub 38 is retained against axial movement on hub 42 by the shoulder Ml on the latter, and by the cap 55, which is retained by under guidance of the roller 36 operating in the cam track 35. The abutting surface 48 on the hub "32 constititutes a lever arm for driving the impeller member. Operation of the impeller member in the opposite direction is effected by a bolt as which has an eye portion 59 arranged between two ears 5|, the sides of which constitute the abutting surface 47 of the hub 38. The bolt s9 is free to pivot about a pin 52 (likewise retained by the cap 45) extending through its eye portion and apertures in the ears 5!. The bolt is extends through an aperture in the abutment 38 and the extending portion carries a compression spring 53 disposed between a washer 54 and a bolt nut 55. The spring 53 provides yieldability in the drive of the impeller member from its recessed position to its position adjacent the stator by permitting overtravel of the cam arm through the compression of the spring. In Fig. 4 this function is illustrated, the abutting members 41 and 438 being spread apart due to the presence of a stone 56 between the forward edge 57 of the impeller and the stator lining 33. The amount of overtravel that is permitted can be predetermined by the selection of the spring and the adjustment of the nut 55 on the bolt 49.

As soon as any appreciable amount of concrete has been propelled through the outlet [9 into the pipeline extending therefrom, pressure starts to build up in the Working chamber define-d by the stripper 29 and the forward faces of the respective impellers 22, as the latter move into full impelling position. This pressure is transmitted against the seals 28 and 36, which are constantly lubricated through the fitting 58 leading through the stator to the space between the rotor seals 28.

Openings 59 are provided in the axial flanges 32 extending outward from the ends of the flanges E5 of the rotor (see Fig. 6) so that lubricant fed to the rotor seals 30 may be transmitted to the impeller seals 28 during operation of the pump. Clearances between the rotor runner and either the stripper or the impeller faces provide only slight pressure relief because of the packing tendency of concrete making these clearances ineifective for relief purposes. Hence the seals must withstand the high pressures created in the chamber if the pressure in the pipeline is to be overcome and the material pumped an appreciable distance.

The overlapping, relation of the replaceable liner 33 to the flanges [5 of the rotor is a factor in prolonging the life of the seals 28 because of the restricted space through which grout may pass before entering the seals in the pressure portion of the pump opposite the stripper. With lubricant constantly fed under pressure into the space between the seals 30, a film of lubricant is formed in the spaces between the liner and the rotor, thereby inhibiting 'the setting up of grout inthis region. By occupying. a portion of the runner, the liner 33 also enables the bi-directional cam 35 to bring the impellers into full impelling position in a shorter periodof time with less throw of the impeller drive means.

I'The position of the impeller members with respect to the rotor and the stator during the 'operation' of the pump is illustrated .in Fig. 1 wherein it will be seen that as each impeller member. passesthe stripping element 20, it is recessed within the rotor. fgu'ideway causes rapid oscillation of the afore- Thereafter the cam said'impellercounterclockwise, as viewed in said figure, 'so'that shortlyafter rotating through 90 the forward edge 51 of the impeller is adjacent the liner 33. The latter position is maintained untilithe rotor has travelled through nearly 270,

the spring 53 in case an obstruction such as a stone is encountered, the movement of the eoncrete through the working chamber is continuous, for there is no time when there are not two impeller members in' full impelling position and the probability of a stone interfering with movement of two successive impellers is practically negligible. If the forward of two impellers is prevented from going into full impelling position, the following impeller will propel the entire channel of concrete ahead of it,

including the most peripheral portion which is not acted upon by the preceding impeller.

The invention having been described, what is claimed is:

l. A rotary pump comprising a stator with an inlet and an outlet and a stripping element therebetween, a rotor spaced from the stator, means confining the ends of the space between the stator and rotor, said rotor having circumferentially spaced impeller members arranged to propel material from the inlet through said space to the outlet of the stator, means for imparting motion to the impeller members to cause them to travel seriatim and with equally positive force in each direction between a position in which they are substantially wholly recessed in the rotor when they are opposite the stripping element and a second position where they are substantially adjacent the stator, and yieldable means limiting travel of the impeller members a predetermined extent when encountering an obstruction during travel to said second position, said means being inoperative during return of said members to recessed position.

2. A rotary pump comprising a stator with an inlet and an outlet and a stripping element therebetween, a rotor spaced from the stator, means confining the ends of the space between the stator and rotor, said rotor having circumferentially spaced impeller members cooperable with said stripping element to propel material from the inlet to the outlet, means for imparting motion to the impeller members to cause them to travel seriatim and with equally positive force in each direction from a position in which they are substantially wholly recessed in the rotor to a second position Where they are substantial ly adjacent the stator, and connections between the motion imparting means and the impeller members providing lost motion during a portion of such travel should the impeller encounter an obstruction, said connection providing positive drive during the entire travel of said members to recessed position.

3. A rotary pump comprising a stator with an inlet and an outlet and a stripping elementth'erebetween, a rotor spaced :from the tstator,;means confining the ends of the space between the :stator and rotor, said rotor having circumferentially spaced impeller. members mountedtherein .arranged to oscillate seriatimbetweena :position in which they are. substantially wholly. recessed in. the rotor whenltheyiare opposite theistripping element and .a tsecondjposition where they .:are

substantially. adjacentthe stator, cam :means "for operating the impeller Im'embers, ..and .;driving means connecting the cam :means and tithe timpeller members providing-an equally positive .drive' of the impeller members: during travel :of

the rotor when they are oppositethe stripping element 'anda second position where they. are

substantially. adjacent .the stator, a stationary bidirectional operatingcamitrack, a cam follower arranged insaid track, a connection between the cam follower and ithe impellenmembers 'oifset with respect to the axes of the latter to produce equally positive oscillatory movement of the impeller members in both directions of travel, in-- cluding over-travel linkage operable for a limited portion of such travel during movement of said members to a position adjacent the stator, and means for varying the amount of such overtravel.

5. A rotary concrete pump comprising a stator with an inlet and outlet and a stripping element therebetween, a rotor spaced from the stator, means confining the ends of the space between the stator and rotor, said rotor having circumferentially spaced impeller members mounted therein arranged to propel concrete through said space from the inlet to the outlet, each of said impellers having a movable drive shaft, a cam for imparting motion to the impeller members to cause them to oscillate from a position in which they are substantially wholly recessed in the rotor when they are opposite the stripping element to a second position where they are substantially adjacent the stator, a lever arm rigid with the impeller drive shaft, a rock arm supported by and pivotal about the axis of the impeller shaft, a cam follower mounted by said rock arm cooperable with said cam, abutting means carried by said arms causing positive drive in one direction, and spring means providing a yieldable connection between said arms while imparting motion in the other direction.

6. In a rotary pump for pumping semi-plastic material such as concrete, a rotor having a cylindrical surface and substantially radial flanges, a stator concentric with said cylindrical surface and spaced therefrom, said stator confining the ends of said flanges to provide a working chamber, impeller members having cylindrical end portions arranged to oscillate within aligned recesses provided in said rotor flanges, sealing means disposed between the ends of the impeller members and the enclosing portions of the rotor flanges, sealing means disposed between the rotor and the stator, means to provide lubricant to the rotor seals, and means to transmit lubricant from the rotor seals to the impeller seals during operation of the pump.

7. A rotary pump for pumping semi-plastic material such as concrete comprising a rotor having a cylindrical surface and substantially radial flanges, a stator enclosing the space between said flanges to provide a pumping chamber and having an inlet and an outlet and a stripper therebetween, a liner member mounted on the stator opposite the stripper, said liner member overlapping and extending between the rotor flanges in closely disposed juxtaposed relation thereto, impeller members having cylindrical end portions arranged to oscillate within aligned recesses provided in the rotor flanges, and means for oscillating the impeller members during movement of the rotor from a position adjacent the stripper to a position adjacent the liner to maintain a pressure chamber communicating with the outlet of the pump,

8. A rotary pump comprising a rotor, a stator concentric with said rotor providing a working chamber therebetween, means confining the ends of said chamber, said stator having an inlet and an outlet and a stripper, impeller members mounted for oscillatory movement in the rotor, a bi-directional cam, cam followers, linkage connecting said followers with the respective impeller members producing equally positive movement of the impellers in each direction of travel,

8 and springs providing overtravel of the linkage should its associated impeller encounter an obstruction, said cam being arranged to maintain at least two impelling members in impelling position at all times, whereby obstruction of one impeller enables the following impeller to maintain pressure in the portion of the working chamber communicating with the outlet of the pump.

CHARLES I. LONGENECKER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 48,604 Umholtz July 4, 1865 549,255 Reichhelm Nov. 5, 1895 1,012,642 Hughes Dec. 26, 1911 1,324,260 Meyer Dec. 9, 919 2,151,484 Nordling Mar. 21, 1949 2,157,141 Murray May 9, 1939 2,168,779 Murray Aug. 8, 1939 2,247,429 Aikman July 1, 1941 2,338,112 Hell Jan. 4, 1944 2,374,445 McFarland Apr. 24, 1945 FOREIGN PATENTS Number Country Date 3,065 Great Britain 1861 243,352 Italy 1926 590,729 France Mar. 25, 1925 

